Flexible optics can be deformed to modify their optical characteristics. For instance, a flexible lens or mirror can be curved or flattened to decrease or increase its focal length. Similarly, various types of flexible optics can be deformed to modify their reflection, refraction, deflection, and transmission characteristics.
In recent years, researchers have used flexible optics to provide advanced optical capabilities in environments where such capabilities were previously unavailable. For example, researchers have used flexible optics to provide advanced zoom capability in miniaturized camera systems found in certain cellular phones, surveillance systems, and robotics applications. This zoom capability is typically achieved by deforming a flexible lens to modify its focal length. Because this lens deformation does not require any translational movement by the entire lens, the zoom capability can be achieved in size-limited applications where translational movement such as that used traditional zoom lens assemblies is not possible.
Flexible optics such as those in the above applications can take a variety of different forms. For instance, they may be formed by any of several commercially available thin clear flexible polymer materials that are molded or cut into a variety of shapes convenient for optics. In some examples, these materials are coated with optical materials to improve their optical performance for specific uses.
While many flexible optics take the form of single film materials, it is also possible to create optics that use a combination of materials. For instance, some flexible optics have been formed by filling an enclosed membrane with a transparent fluid such as water, oil, or air. A liquid lens is an example. The optical properties of these types of optics can be adjusted, for example, by adjusting the diameter of a lens, or changing the amount of fluid in the membrane to modify the membrane's internal pressure.
Although researchers have successfully employed flexible optics in a variety of different environments, the performance and reliability of these flexible optics is typically limited by the performance and reliability of mechanical components used to control their deformation. For instance, the speed and precision with which a flexible lens can be deformed is generally determined by the response-time and accuracy of mechanical components used to control the lens's deformation. Similarly, the failure rate of an optical system including a flexible lens may be limited by the lifetime of the controlling mechanical components.
To illustrate some of the limitations imposed by traditional mechanical components, consider an optical system in which a flexible lens is deformed under the control of a small motor. The motor will typically experience some form of gear lash or hysteresis that will limit the speed and accuracy of its movement. Additionally, the motor may fail before the end of the lens's effective lifetime. Further, the motor is likely much thicker than the flexible lens, and therefore the motor will likely limit the degree to which the optical system can be miniaturized. Moreover, the cost of the motor is likely very high compared with the cost of the flexible lens. Finally, the motor may require a relatively complex control system to control its movement.
Most conventional optical systems using flexible optics suffer from some or all of the above mechanical problems. Accordingly, a need exists for techniques and technologies that overcome the above problems, as well as ones that provide additional benefits. Overall, the examples herein of some prior or related technologies and their associated limitations are intended to be illustrative and not exclusive. Other limitations of existing or prior technologies will become apparent to those of skill in the art upon reading the following Detailed Description.